Anticipation strategies of motor control in children and adolescents with cerebellar pathologies and typical development: a dual task paradigm.

BACKGROUND: Besides ataxia, cerebellar pathologies are often associated with neuropsychological deficits, particularly in executive attention. The cerebellum is considered a key hub of the predictive brain network, interacting with prefrontal and parietal areas through the basal ganglia. Anticipating the sensory consequences of motor actions and comparing them with actual feedback supports feedforward control, improving coordination, processing speed, and reducing errors. It also contributes to integrating subcortical-cortical networks during dual-task conditions. We hypothesized that impaired anticipatory strategies contribute to motor control deficits in cerebellar patients. Specifically, fine upper-limb motor control would worsen when combined with concurrent neuropsychological and cerebellar tasks (verbal anticipation and timing), compared with a working memory task or a single motor task. Therefore, we aimed to investigate dual-task abilities in cerebellar patients.

METHOD: In total, 24 participants affected by cerebellar pathologies (mean age was 13y 1 m; 16 females) and 24 participants with typical development (mean age was 13y 1 m; 14 females) were required to execute a single visuo-motor precision task (single task condition) alone and with concurrent verbal anticipation, verbal timing, and verbal nBack tasks. Execution time and accuracy were analyzed as dependent variables combined in a single index [Inverse Efficacy, IE = RT/(1-pE)] and separately.

RESULTS: The results showed that the dual-task condition negatively affects the fine motor control of the upper limb in the two groups. A significant negative effect of the anticipation task was found for both the cerebellar and control groups. The cerebellar group presented a significant negative effect on the nBack task as well.

DISCUSSION: The results are consistent with the models describing the cerebellum as a key hub in anticipatory control, probably through predictive network synchronization. The anticipatory control is a damaged component in the control deficit of cerebellar patients. Finally, the cerebellar role in synchronizing the different cerebral networks involved in dual-task processing is strengthened. This study underlines the crucial role of anticipatory and feedforward mechanisms in motor control of both typically developed children and those with cerebellar pathologies and defines the importance of predictive neuropsychological skills in cognitive and motor fluidity.